Pipe end fitting with improved venting

ABSTRACT

A pipe end fitting assembly that includes an outer body having an outer surface, an inner surface defining a first bore, and an end surface, and an inner body having an inner surface defining a second bore and an outer surface. A portion of the inner body outer surface is secured to the outer body inner surface. A passage formed in the outer body includes a first portion extending from the end surface and parallel to the first bore, and a second portion extending from the outer body outer surface to the passage first portion. A pipe end is disposed around and secured to a portion of the inner body outer surface. A jacket is disposed around the pipe and has an end secured to the outer body outer surface. The passage portions are in fluid communication with each other and a space between the jacket and the pipe.

RELATED APPLICATIONS

This application is a divisional of U.S. Non-Provisional applicationSer. No. 13/644,891 filed on Oct. 4, 2012, which claims the benefit ofU.S. Provisional Application No. 61/543,247, filed Oct. 4, 2011, thecontents of each of which are incorporated by reference herein in theirentirety

FIELD OF THE INVENTION

The present invention relates to pipe end fittings, and moreparticularly to a pipe end fitting for use with pipes having an externaljacket for capturing any leaked liquid or gas.

BACKGROUND OF THE INVENTION

FIG. 1 is a cross sectional view illustrating a conventional pipe endfitting 1. The end fitting 1 is machined from a single piece of stock,such as carbon or stainless steel. The end fitting includes a centerbore 2, a securing end 4 and a pipe attachment end 6. An annularconnector notch 12 is formed on the outer surface near the securing end4 for securing the end fitting 1 to its destination (e.g. a well headvalve). The fitting 1 also includes a serrated pipe connector 14 at thepipe attachment end 6 for receiving and securing the end of an innerpipe 16 of a pipe assembly 18. The pipe assembly 18 additionallyincludes a jacket 20 surrounding the inner pipe 16. Jacket 20 provides acompression fit for the connection of the pipe assembly 18 to endfitting 1, and captures any liquids or gasses that may have leaked fromthe inner pipe 16. A weld 22 is used to secure jacket 20 to the endfitting 1. The jacket 20 includes a vent port 24 extending therethroughnear the weld 22. The vent port 24 is used to vent any leakedliquid/gasses captured by the jacket 20.

There are several disadvantages of the illustrated conventional endfitting 1. Because of the length and width of the end fitting 1,machining the end fitting 1 from a single piece of stock material iscostly, time consuming, and wasteful of stock material. In addition, thevent port 24 formed in the jacket 20 can be deformed during the swageprocess used to mount the pipe assembly 18 to the end fitting 1, whichcan cause the vent port 24 to leak.

There is a need for an improved end fitting that addresses the abovementioned issues.

BRIEF SUMMARY OF THE INVENTION

The aforementioned problems and needs are addressed by a pipe endfitting assembly that includes an outer body having an outer surface, aninner surface defining a first bore, and an end surface extendingbetween the inner and outer surfaces. An inner body has an inner surfacedefining a second bore and an outer surface, wherein a first portion ofthe inner body outer surface is secured to the outer body inner surface.A passage is formed in the outer body extending from the end surface tothe outer surface of the outer body, wherein the passage includes afirst portion extending from the end surface and parallel to the firstbore, and a second portion extending from the outer surface of the outerbody to the first portion of the passage, wherein the first and secondportions of the passage are in fluid communication with each other.

In another aspect of the invention, a pipe assembly includes an outerbody having an outer surface, an inner surface defining a first bore,and an end surface extending between the inner and outer surfaces. Aninner body has an inner surface defining a second bore and an outersurface, wherein a first portion of the inner body outer surface issecured to the outer body inner surface. A passage is formed in theouter body extending from the end surface to the outer surface of theouter body, wherein the passage includes a first portion extending fromthe end surface and parallel to the first bore, and a second portionextending from the outer surface of the outer body to the first portionof the passage. A pipe has an end disposed around and secured to asecond portion of the inner body outer surface. A jacket disposed aroundthe pipe and having an end secured to the outer body outer surface. Thefirst and second portions of the passage are in fluid communication witheach other and with a space extending between the jacket and the pipe.

In yet another aspect of the invention, a method of forming a pipeassembly includes forming an outer body having an outer surface, aninner surface defining a first bore, and an end surface extendingbetween the inner and outer surfaces, forming a passage in the outerbody extending from the end surface to the outer surface of the outerbody, wherein the passage includes a first portion extending from theend surface and parallel to the first bore, and a second portionextending from the outer surface of the outer body to the first portionof the passage, forming an inner body having an inner surface defining asecond bore and an outer surface, securing a first portion of the innerbody outer surface to the outer body inner surface, securing an end of apipe around and to a second portion of the inner body outer surface, andsecuring an end of a jacket to the outer body outer surface, wherein thejacket is disposed around the pipe. The first and second portions of thepassage are in fluid communication with each other and with a spaceextending between the jacket and the pipe.

Other objects and features of the present invention will become apparentby a review of the specification, claims and appended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side cross sectional view of a conventional pipe endfitting.

FIG. 2 is a side cross sectional view of the pipe end fitting assemblyof the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is pipe end fitting assembly 30, which isillustrated in FIG. 2. The pipe end fitting assembly 30 constitutes twoseparate components that are affixed to each other: the outer body 32and the inner body 34.

The outer body 32 is generally cylindrically shaped having an innersurface 32 a that defines a bore 36 extending longitudinally through theouter body. A connector notch 38 is formed on the outer surface 32 b ofouter body 32 (to facilitate connection to its destination). The innerbody 34 is generally cylindrically shaped with an inner surface 34 athat defines a bore 40 extending longitudinally through the inner body34. One end of the inner body 34 has serrations on the outer surface 34b of the inner body 34, forming a serrated pipe connector 42 (forreceiving and securing a pipe end). The other end of the inner body 34is disposed in bore 36 and mounted to the outer body 32. Specifically,the outer surface 34 b of inner body 34 is secured to the inner surface32 a of the outer body 32, preferably with a press-fit (i.e. shear forcebetween the inner surface 32 a of outer body 32 and the outer surface 34b of inner body 34, creating an interference fit therebetween). Theinterference fit can optionally be temperature enhanced, where one ofthe inner/outer bodies is heated and the other is cooled before beingfitted together so additional compressive forces are generated afterbeing fitted together as they equalize in temperature. Optional welds 44can be formed at the edges of the inner/outer bodies 32/34, whichconstitute a redundant seal to contain pressurized liquids/gasses.Serrations or threads could additionally or alternatively be used tosecure the outer and inner bodies 32/34 together for enhanced tensilecapacity.

A pipe assembly 46 connects to the pipe end fitting 30. Pipe assembly 46includes an inner pipe 48 and a jacket 50 surrounding the inner pipe 48.The end of the inner pipe 48 slides over and engages the serrated pipeconnector 42. The end of the jacket 50 is secured to the outer body 32by a weld 52. Any liquids or gasses that leak out of pipe 48 and intothe space 53 between pipe 48 and jacket 50 are captured by jacket 50 andguided to the end fitting assembly 30.

A vent passage 54 is formed through the outer body 32, providing ventingfor space 53. Preferably, passage 54 includes a first passage portion 54a extending longitudinally within the outer body 32 (parallel to bore36), and a second passage portion 54 b extending outwardly from thefirst passage portion 54 a to the outer surface 32 b of outer body 32(i.e. first and second passage portions 54 a/54 b are orthogonal to eachother). The formation of the first passage portion 54 a was not feasiblein the conventional design of FIG. 1 because the excessive length of theserrated pipe connector 14 blocked access to the surface in which such apassage could be made (i.e. most drilling or material removing machineryrequires full access to the surface in which drilling or materialremoval is to be performed). However, with the design of FIG. 2, firstpassage portion 54 a can be reliably made in outer body 32 before it ismounted to inner body 34, where end surface 56 of outer body 32 (intowhich first passage portion 54 a is formed) is fully accessible.Likewise, second passage portion 54 b is machined into the outer surface32 b of outer body 32 (which is fully accessible as well) until the twopassage portions 54 a/54 b meet. Passage 54 provides fluid communicationbetween space 53 and the outer surface 32 b of outer body 32, whereleaked liquids or gasses in space 53 can be vented and captured. Themulti-portion passage 54 is far more reliable than the conventionaltechnique of forming the vent port in the jacket itself, whereunintended deformation and leaking can occur.

Another advantage of the forming end fitting assembly 30 using twoseparate bodies 32/24 attached together is the optimization/minimizationof material stock used to make end fitting assembly 30. Smallerdimensioned stock material can be used to individually form the innerand outer bodies 32/24, which significantly lowers the amount of stockmaterial that is wasted compared to machining the end fitting as asingle piece of material. The machining processes for fabricating theinner and outer bodies 32/34 is simplified, making them faster and lessexpensive to make compared to the single piece end 10 fitting of FIG. 1.

It is to be understood that the present invention is not limited to theembodiment(s) described above and illustrated herein, but encompassesany and all variations falling within the scope of the appended claims.For example, references to the present invention herein are not intendedto limit the scope of any claim or claim term, but instead merely makereference to one or more features that may be covered by one or more ofthe claims. Materials, processes and numerical examples described aboveare exemplary only, and should not be deemed to limit the claims.Further, as is apparent from the claims and specification, not allmethod steps need be performed in the exact order illustrated orclaimed, but rather in any order that allows the proper formation of thepipe end fitting of the present invention.

What is claimed is:
 1. A method of forming a pipe assembly, comprising:forming an outer body having an outer surface, an inner surface defininga first bore, and an end surface extending between the inner and outersurfaces; forming a passage in the outer body extending from the endsurface to the outer surface of the outer body, wherein the passageincludes a first portion extending from the end surface and parallel tothe first bore, and a second portion extending from the outer surface ofthe outer body to the first portion of the passage; forming an innerbody having an inner surface defining a second bore and an outersurface; securing a first portion of the inner body outer surface to theouter body inner surface; securing an end of a pipe around and to asecond portion of the inner body outer surface; and securing an end of ajacket to the outer body outer surface, wherein the jacket is disposedaround the pipe; wherein the first and second portions of the passageare in fluid communication with each other and with a space extendingbetween the jacket and the pipe.
 2. The method of claim 1, wherein thesecuring of the first portion of the inner body outer surface to theouter body inner surface is performed after the forming of the passage.3. The method of claim 1, wherein the second portion of the passageextends orthogonally to the first portion of the passage.
 4. The methodof claim 1, wherein the first and second bores are cylindrically shaped.5. The method of claim 1, further comprising: forming a weld between theend surface to the inner body outer surface.
 6. The method of claim 1,wherein the inner body first portion terminates at a first end, andwherein the method further comprises: forming a weld between the firstend and the outer body inner surface.
 7. The method of claim 1, furthercomprising: forming a notch into the outer surface of the outer body. 8.The method of claim 1, further comprising: forming serrations into thesecond portion of the inner body outer surface before the securing ofthe pipe thereto, wherein the outer body is a single piece and whereinthe first portion of the passage is a unitary first portion.
 9. Themethod of claim 1, wherein the inner body is disposed between the outerbody and the second bore.
 10. The method of claim 1, wherein the passageis unencumbered and allows for direct passage of liquid or gastherethrough.